Why Earth's shortest day could affect your GPS
On August 5, 2025, Earth finished its spin 1.33 milliseconds faster than usual—making it one of the shortest days on record.
This quickened pace is part of a surprising trend since 2020 that goes against what scientists expected (they thought Earth's rotation would slow down over time).
What caused the speed-up?
A mix of things: slower winds during northern summer, ocean currents, and a rare Moon position that reduced the usual "braking" effect from lunar tides.
Plus, shifts deep inside Earth—between its core and mantle—gave an extra boost to our planet's spin.
Why it matters
Even tiny changes in Earth's rotation mess with tech we use every day, like GPS and satellites.
Scientists track these shifts using atomic clocks and sometimes add leap seconds to keep everything synced.
Without those tweaks, your maps or navigation apps could be off by more than half a meter at the equator—so yeah, it matters!